Seabirds as ‘ocean sentinels’ for measuring climate change impacts on marine ecosystems

Ascension Island is one of the most important seabird breeding stations in the tropical Atlantic; home to an estimated 1 million individuals from 11 species.

During the breeding season, seabirds are limited in the distance they can travel in search of food by the need to regularly return to land and care for dependent chicks. As a result, their breeding success tends to be very sensitive to fluctuations in local food supply within reach of the nesting colony.

Because chick survival is relatively easy to monitor for land-based observers, seabirds are often regarded as ‘sentinel species’ for tracking changes in offshore marine food webs that are difficult to measure directly.

By identifying the environmental factors that drive current variability in seabird productivity and combining this information with long-term forecasts from oceanographic models, the CRACAB team hopes to understand how a changing climate might impact both Ascension’s seabirds and the wider marine ecosystem they depend upon.

Keep checking the blog for update on how this work package progresses.

The stats


1 million Estimated number of seabirds nesting at Ascension Island (Ratcliffe et al. 2009)


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